title: Enhanced biofuel production from high-concentration bioethanol wastewater by a newly isolated heterotrophic microalga, Chlorella vulgaris LAM-Q.
abstract: Microalgal biofuel production from wastewater has economic and environmental advantages. This article investigates the lipid production from high chemical oxygen demand (COD) bioethanol wastewater without dilution or additional nutrients, using a newly isolated heterotrophic microalga, Chlorella vulgaris LAM-Q. To enhance lipid accumulation, the combined effects of important operational parameters were studied via response surface methodology. The optimal conditions were found to be temperature of 22.8℃, initial pH of 6.7, and inoculum density of 1.2 × 10(8) cells/ml. Under these conditions, the lipid productivity reached 195.96 mg/l/d, which was markedly higher than previously reported values in similar systems. According to the fatty acid composition, the obtained lipids were suitable feedstock for biodiesel production. Meanwhile, 61.40% of COD, 51.24% of total nitrogen, and 58.76% of total phosphorus were removed from the bioethanol wastewater during microalgal growth. In addition, 19.17% of the energy contained in the wastewater was transferred to the microalgal biomass in the fermentation process. These findings suggest that C. vulgaris LAMQ can efficiently produce lipids from high-concentration bioethanol wastewater, and simultaneously performs wastewater treatment.
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Tonghui
authors.initials: T
authors.lastname: Xie
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Kaifeng
authors.initials: K
authors.lastname: Du
authors.forename: Bin
authors.initials: B
authors.lastname: Liang
authors.forename: Yongkui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D056804:Biofuels; D001709:Biotechnology / Q000379:methods; D048408:Chlorella vulgaris / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D050356:Lipid Metabolism; D013696:Temperature; D062065:Wastewater / Q000382:microbiology*; D014873:Water Pollutants / Q000378:metabolism*
chemical_list: D056804:Biofuels; D005227:Fatty Acids; D062065:Wastewater; D014873:Water Pollutants